The pace of deforestation in Colombia has accelerated over the past 20 years, even as population growth has slowed and the economy has shifted from agriculture to other revenue sources, Dávalos says.

Colombia accounted for 75 percent of the world’s coca in 2000. Earlier reports found that direct deforestation from coca was surprisingly small, with as little as 150 square kilometers of forests replaced by coca each year by 2005.

Since rainforests contain about 10 percent of the world’s plant and animal species—some of which become the basis of new medicines—deforestation represents a serious threat to global biodiversity.

For the study, Dávalos analyzed data from 2002-2007 on the effects of coca cultivation on deforestation of rainforests in Colombia and identified several factors that boosted the likelihood that rainforests would be destroyed.

In southern Colombia, a forest close to newly developed coca farms, for instance, was likely to be cut, as was land in areas where much of the farmland was devoted to coca.

This is the first time the indirect impact on deforestation from cultivation destined for the global cocaine market has been quantified across South America’s biodiversity hotpots.

Designating larger protected areas, regions that are set-aside for special protection for environmental reasons, reduces forest destruction in coca-growing areas and could further help control deforestation and preserve biodiversity, the report suggests.